Agricultural implement and method of operating agricultural implement

Abstract

An agricultural implement (1) comprises an implement frame (10, 11, 13a, 13b, 13c) has a first side frame section (13a; 13b), and a second side frame section (13b; 13c), which is pivotably connected to the first side frame section (13a; 13b) about an inter-frame pivot axis (Pa, Pb) which is horizontal and parallel with a working direction (Dw) of the agricultural implement (1). Each of the side frame sections (13a, 13b, 13c) carries a plurality of tool units (14, 14a-14j), and at least one of the tool units (14, 14a-14j) is connected to the implement frame by a parallel linkage (141) comprising at least two lower links (1411, 1412) and at least one upper link (1413). A first one of the lower links (1411, 1412) is pivotably connected to the first side frame section (13a; 13b). A second one of the lower links (1411, 1412) is pivotably connected to the second side frame section (13b; 13c). The upper link is (1413) pivotably connected to at least one of the first side frame section (13a; 13b) and the second side frame section (13b; 13c). The lower links (1411, 1412) connect to the respective side frame section (13a, 13b, 13c) at approximately a same vertical level as the inter-frame pivot axis. There is also disclosed a method of operating an agricultural implement (1).

Description

[0001] AGRICULTURAL IMPLEMENT AND METHOD OF OPERATING AGRICULTURAL IMPLEMENT

[0002] Technical field

[0003] The present disclosure relates to agricultural implements and in particular to agricultural implements having frame sections that are movable, such as pivotable, relative to each other, so as to allow the agricultural implement to follow undulations of the ground over which the agricultural implement travels.

[0004] Background

[0005] Agricultural implements are known which have a plurality of tools or tool units distributed over a width of the implement. A particular class of such agricultural implements include agricultural implements which have tool units in the form of output units that are configured for distributing a product to ground over which the agricultural implement travels. To this end, the output units may engage the ground, e.g. to provide a furrow into which the product is dispensed and optionally to close the furrow into which the product has been dispensed.

[0006] As it is desirable to increase precision in the dispensing of the product, output units are becoming increasingly complex. The use of such complex output units for planting crops which can be planted in laterally closely spaced rows provides challenges in the design of the agricultural implement. For example, the close spacing of output units in combination with the desire to produce larger agricultural implements, which have a greater width across a working direction, presents a challenge in that the frame of the agricultural implement needs to be able to conform to variations in ground height across the width of the agricultural implement. To this end, lateral pivot joints may be provided, such that frame sections may pivot relative to each other about a horizontal axis that it approximately parallel with the working direction. The dimensions needed to provide a pivot joint having sufficient strength and pivot range, however, give rise to a lateral gap between adjacent frame sections, which may be close to or greater than the spacing between adjacent output units, such that it is difficult to achieve an even spacing between the output units across the entire width of the agricultural implement. Hence, there is a need for a solution that makes it possible to provide an agricultural implement with pivot joints that allow for ground compliance while allowing a close and uninterrupted lateral spacing between tool units.

[0007] It is an objective of the present disclosure to provide solutions which eliminate or alleviate at least some of the disadvantages mentioned above. A particular objective is to provide a solution which allows for laterally close spacing of tool units, in combination with pivot joints for ground compliance.

[0008] The invention is defined by the appended independent claims. Embodiments are set forth in the appended dependent claims, in the following description and in the attached drawings.

[0009] According to a first aspect, there is provided an agricultural implement, comprising an implement frame having a first side frame section, and a second side frame section, which is pivotably connected to the first side frame section about an inter-frame pivot axis which is horizontal and parallel with a working direction of the agricultural implement, wherein each of the side frame sections carries a plurality of tool units, and wherein at least one of the tool units is connected to the implement frame by a parallel linkage comprising at least two lower links and at least one upper link. A first one of the lower links is pivotably connected to the first side frame section. A second one of the lower links is pivotably connected to the second side frame section. The upper link is pivotably connected to at least one of the first side frame section and the second side frame section. The lower links connect to the respective side frame section at approximately a same vertical level as the interframe pivot axis.

[0010] A tool unit may be an output unit, such as a row unit or other arrangement for distributing a product to ground over which the agricultural implement travels. Alternatively, a tool unit may comprise a reconsolidation tool, a tillage tool or a row cleaning tool.

[0011] A tool unit may be connected to a leading edge of a side frame section, as may be the case with a reconsolidation tool, or to a trailing edge of a side frame section, as would normally be the case with an output unit. The parallel linkage may comprise a single upper link. Alternatively, the parallel linkage may comprise a pair of upper links, which may be connected to a respective one of the frame sections.

[0012] By connecting the lower links to the respective frame section at approximately the same vertical level as the inter-frame pivot axis, it is possible to position a tool unit such that it bridges the gap between the frame sections without the pivot links being subjected to excessive offsets as the side frame sections pivot relative to each other.

[0013] Hence, it is possible to provide an agricultural implement which is able to flexibly follow variations in ground level, also with laterally closely spaced tool units.

[0014] The lower links may connect to the respective side frame sections within a frame height of at least one of the side frame sections.

[0015] In particular, the lower links may connect within the vertical frame height closest to the inter-frame pivot axis. Portions of a frame which protrude locally and / or far spaced from the inter-frame pivot axis may be disregarded when determining what the frame height is.

[0016] The lower links may connect to the respective side frame sections within a vertical distance from the inter-frame pivot axis, which is less than about 50 % of the frame height, preferably less than about 25 % of the frame height, less than about 10 % of the frame height or less than about 5 %.

[0017] At least one of the lower links and the inter-frame pivot axis may be positioned vertically centrally of at least one of the side frame sections.

[0018] The agricultural implement as claimed in any one of the preceding claims, wherein the tool units comprise at least some tool units, which are in the form of output units, configured for distributing a product to ground over which the agricultural implement travels.

[0019] Such output units may comprise row units or other types of output units, in particular for granular materials, such as seeds, fertilizer or pesticide.

[0020] The side frame sections may be configured to allow a limited pivoting action about the inter-frame pivot axis, preferably of less than about + / - 30 degs, less than about + / - 20 degs, less than about + / - 15 degs, less than about + / - 10 degs or less than about + / - 5 degs. Hence, the side frame sections and in particular the inter-frame pivot axis, may be configured only for allowing the frame sections to following ground undulations, but not for allowing folding of the agricultural implemnet about such axis.

[0021] Each of the tool units may be connected to the implement frame by a respective parallel linkage comprising at least two lower links and at least one upper link.

[0022] Laterally adjacent tool units may present parallel linkages of different lengths, such that adjacent tool units are longitudinally offset along the working direction.

[0023] The parallel linkage, the first and second lower links of which connect to the first and second side frame sections, respectively, is longer than those of immediately laterally adjacent tool units.

[0024] "First and second lower links" may hereby be equal to "first lower link and second lower link".

[0025] Analoguously, "first and second side frame sections" may hereby be equal to "first side frame section and second side frame section". This should be construed as indexing of side frame sections, rather than frame sections of first and second sides.

[0026] The lower links may be fixedly connected to each other, in particular formed in one piece.

[0027] The agricultural implement may comprise at least one actuator configured for controlling a movement about the inter-frame pivot axis.

[0028] One of the first side frame section and the second side frame section may comprise a mounting flange, to which the upper link is pivotably connected.

[0029] In some embodiments, only one of the first side frame section and the second side frame section may present the mounting flange.

[0030] The mounting flange may present a portion, which extends laterally towards the other one of the first side frame section and the second side frame section, and to which the upper link is pivotably connected.

[0031] In some embodiments, both of the first side frame section and the second side frame section may present a respective mounting flange and the upper link may be pivotably connected to both of the mounting flanges. For example, a pivot rod may be pivotably connected and axially fixed to one of the mounting flanges and pivotably and axially movably connected to the other one of the mounting flanges, wherein the upper link is connected to the pivot rod.

[0032] According to a second aspect, there is provided a method of operating an agricultural implement, having an implement frame comprising a first side frame section, a second side frame section, which is pivotably connected to the first side frame section about an inter-frame pivot axis which is horizontal and parallel with a working direction of the agricultural implement. Each of the side frame sections carries a plurality of tool units, and at least one of the tool units is connected to the implement frame by a parallel linkage comprising a pair of lower links and at least one upper link. The method comprises causing the side frame sections to pivot relative to each other about the inter-frame pivot axis, and causing the parallel linkage to pivot relative to the side frame sections about a pair of lower link pivot axes, that are vertically aligned with the inter-frame pivot axis and that are connected to a respective one of the side frame sections.

[0033] Fig. 1 is a schematic top view of an agricultural implement.

[0034] Fig. 2 is a schematic perspective view of a part of the agricultural implement. Figs 3a-3b schematically illustrate a two pairs of laterally adjacent output units.

[0035] Figs 4a-4b schematically illustrate side views of an output unit.

[0036] Fig. 5 schematically illustrates the part of the agricultural implement with output units removed.

[0037] Figs 6a-6b schmeatically illustrate the part of the agricultural implement with frame sections 13a, 13b in a mutually planar state.

[0038] Figs 7a-7b schmeatically illustrate the part of the agricultural implement with frame sections 13a, 13b in a mutually downwardly concave state.

[0039] Figs 8a-8b schmeatically illustrate the part of the agricultural implement with frame sections 13a, 13b in a mutually downwardly convex state.

[0040] Figs 9a-9b schmeatically illustrate the part of the agricultural implement with frame sections 13a, 13b in a mutually planar state. Figs lOa-lOb schmeatically illustrate the part of the agricultural implement with frame sections 13a, 13b in a mutually downwardly concave state.

[0041] Figs lla-llb schmeatically illustrate the part of the agricultural implement with frame sections 13a, 13b in a mutually downwardly convex state.

[0042] Figs 12a-12b schmeatically illustrate the part of the agricultural implement with frame sections 13a, 13b in a mutually planar state.

[0043] Figs 13a-13b schmeatically illustrate the part of the agricultural implement with frame sections 13a, 13b in a mutually downwardly concave state.

[0044] Figs 14a-14b schmeatically illustrate the part of the agricultural implement with frame sections 13a, 13b in a mutually downwardly convex state.

[0045] Detailed description

[0046] Throughout this specification, unless the context requires otherwise, the word "comprise", or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated element, integer or step, or group of elements, integers or steps, but not the exclusion of any other element, integer or step, or group of elements, integers or steps.

[0047] The terms "a" and "an" are used herein to refer to one or to more than one (i.e. to at least one) of the grammatical object of the article. By way of example, "an element" means one element or more than one element.

[0048] In the context of this specification, modifying terms, such as "about", "approximately", "substantially", and other approximators, are understood to refer to a range of numbers that a person of skill in the art would consider equivalent to the recited value in the context of achieving the same function or result. Any value, range or term thus modified is to be understood as being disclosed also without the modifying term.

[0049] In the following description, the concept will be described with reference to an agricultural implement 1 comprising output units configured for distributing a product, in particular seeds, to relatively closesly spaced rows. However, the concept may also be used for other types of output units, including row units, as well as to other types of tool units.

[0050] The agricultural implement 1 may comprise an implement frame 10, which may comprise a main frame section 11, a coupling 12 and a tool carrying frame 13a, 13b, 13c. Optionally, ground supports 15a, 15b, such as wheels or rollers, may be provided for supporting the agricultural implement towards the ground over which it travels, e.g. in order to provide a predetermined vertical distance between the frame and the ground.

[0051] The frame 13a, 13b, 13c may be formed by one or more beams, and may comprise at least one transversely (relative to the working direction Dw) extending beam, along which tools, such as output units 14a-14j, may be attached. Each tool, and in particular each output unit, may be movably connected to the frame by a linkage arrangement 141.

[0052] The agricultural implement 1 may be configured for being towed, or wholly or partially carried by a traction vehicle (not shown). The agricultural implement may also be designed for being used with a gantry type traction vehicle, or as a self-propelled autonomous implement.

[0053] In orderto enable the agricultural implement 1 to follow undulations of the ground over which the agricultural implement 1 travels, the tool carrying frame may be divided into two or more side frame sections 13a, 13b, 13c, which are pivotably connected to each other about an inter-frame pivot joint 131a, 131b, which may provide an inter-frame pivot axis Pa, Pb that is horizontal and approximately parallel with a working direction Dw of the agricultural implement 1.

[0054] An agricultural implement 1 may comprise multiple implement portions comprising two or more side frame sections 13a, 13b 13c connected to each other as described above.

[0055] Implement portions may overlap such that a side frame section 13b is part of multiple implement portions.

[0056] Fig. 1 illustrate a first implement portion comprising a first side frame section 13a and a second side frame section 13b, which are pivotably connected to each other about an inter-frame pivot joint 131a, which provides an inter-frame pivot axis Pa.

[0057] Fig. 1 also illustrate a second implement portion comprising a first side fram section 13b and a second side fram section 13c, which are pivotably connected to each other about an inter-frame pivot joint 131b, which provides an inter-frame pivot axis Pb. The same side frame section may constitute a first side frame section in a first implement portion and a second side frame section in a second implement portion. This is examplified by side frame section 13b in Fig. 1.

[0058] Hence, through this inter-frame pivot joint 131a, 131b, side frame sections 13a, 13b, 13c may pivot slightly relative to each other. For example, the inter-frame pivot joint 131 may allow for a pivoting of less than about + / - 30 degs, less than about + / - 20 degs, less than about + / - 15 degs, less than about + / - 10 degs or less than about + / - 5 degs.

[0059] A movement about the inter-frame pivot joint 131a, 131b may be controlled by an actuator 132a, 132b, such as a hydraulic actuator, which may operate between flanges provided on the side frame sections 13a, 13b, 13c. Alternatively, a biasing device, such as a spring, may be provided instead of, or in addition to, the actuator.

[0060] In the illustrated example, the side frame sections 13a, 13b, 13c are formed as an essentially 2D lattice arrangement of beams that extend at least transversely and longitudinally, and that may be joined by welding. A height hv (fig. 5) of a side frame section may be defined as a height of the vertically thickest beam forming the side frame section.

[0061] However, the inventive concept may be used also on frame sections 13a, 13b, 13c comprising a single transverse beam, as is common for planters.

[0062] A plurality of output units 14a-14j are distributed over the width of the side frame sections 13a, 13b. Each output unit 14a-14j is connected to a side frame section 13a, 13b, 13c by a parallel linkage 141. A biasing device 142, such as an actuator or a spring may be provided for biasing the output unit 14, 14a-14j towards the ground. The biasing device 142 may also be used to control a force by which the output unit is pressed towards ground, and / or to lift the output unit out 14a-14j of the ground, if desired.

[0063] Each of the output units 14a-14j may comprise an output unit frame 140, to which the links of the parallel linkage 141 may be pivotably connected. Alternatively, the output unit frame 140 may be integrated with e.g. the lower links, such that the entire output unit frame 140 is pivotable relative to the frame.

[0064] Fig. 2 schematically illustrates a pair of side frame sections 13a, 13b, which are connected by a pivot joint 131a, which is horizontal and parallel with a working direction Dw of the agricultural implement. Fig. 2 does not illustrate any embodiment of the agricutural implement 1, but rather an embodiment of how a plurality of output units 14c-14h may be connected to a pair of frame sections 13a, 13b.

[0065] A plurality of output units 14c-14h are mounted to the frame sections 13a, 13b, with one (14c) of the illustrated output units being mounted to the first frame section 13a, one (14d) being mounted across the pivot joint 131a and the remainder (14e-14h) of the output units being mounted to the second frame section 13b.

[0066] In the illustrated example, laterally adjacent output units 14, 14a-14j may have parallel linkages 141, 141E with different lengths, such that laterally adjacent output units 14, 14a-14j may be offset in the working direction Dw, which may enable a closer lateral spacing of the output units 14, 14a-14j.

[0067] Referring to figs 3a-3b, each of the parallel linkages 141 may comprise a pair of lower links 1411, 1412, which are laterally spaced apart, and one upper link 1413. Each of the links 1411, 1412, 1413 may be pivotably connected to the side frame section 13a, 13b and optionally to an output unit frame 140.

[0068] The lower links 1411, 1412 may be connected to each other, e.g. by being integrated. To this end, the lower links 1411, 1412 may be formed in one piece of material.

[0069] Figs 3a-3b schematically illustrate two pairs of output units 14a, 14b; 14c, 14d, which may form part of a larger set of output units. As can be seen from figs 3a-3b, the output units are arranged with their output unit frames 140 at different longitudinal positions along the working direction Dw, such that immediately adjacent output units 14a, 14b; 14c, 14d are longitudinally offset. This arrangement is achieved by using the same configuration for the output units 14a-14d as such, but with different parallel linkages 141, 141E, where the parallel linkages 141E of the rearwardly arranged output units 14b, 14d are extended as compared to the parallel linkages 141 of the forwardly arranged output units 14a, 14c.

[0070] In particular, the lower links 1411, 1412 may, but need not, correspond to a single lower link 1411E, which may be provided with a bifurcation at its forward end, such that its forward connectors correspond to forward connectors of the parallel linkage 141 of the forwardly arranged output units 14a, 14c. Moreover, the extended lower link 1411E may be reinforced, e.g. to provide increased bending stiffness as compared to the lower links 1411, 1412.

[0071] Similarly, the extended upper link 1413E may correspond to the upper link 1413, optionally with increased bending stiffness.

[0072] Referring to figs 4a-4b, the output unit 14, 14a-14j, and in particular the output unit frame 140, may support a furrow opener 143, which may take the form of one or a pair of discs, as illustrated, and / or which may be provided as a seed knife or other type of coulter.

[0073] The output unit 14, 14a-14j may further comprise a seed tube 144, which, as illustrated, may be connected to a coulter 1441, or which may be merely a tube, which may be rearwardly bent and protected by the seed disc(s).

[0074] The output unit 14, 14a-14j may further comprise one or more gauge devices 145, such as gauge wheels, configured for limiting a working depth of the furrow opener 143. The gauge device 145 may comprise a gauge wheel 1451, which may be supported by a gauge wheel arm 1452.

[0075] The output unit 14, 14a-14j may further comprise a press device 146 configured for pressing the product into contact with the soil. The press device 146 may be formed as a press wheel 1461, which may be supported by a press wheel arm 1462.

[0076] The output unit may further comprise a furrow closer 147 configured for closing a furrow formed by the furrow opener. The furrow closer 147 may be formed as one or a pair of wheels 1471, which may be supported by a furrow closer arm 1472.

[0077] The output unit 14, 14a-14j may further comprise a metering device 148, which may be configured to meter product that is output throught the seed tube 144, such that a precise amount of the product is provided, e.g. a precise number of seeds, or an even volume flow of seeds.

[0078] Referring to fig. 5, the arrangement of the linkages 141, 141E is more readily visible.

[0079] The inter-frame pivot joint 131a, 131b may be positioned vertically such that the inter-frame pivot axis Pa, Pb provided is within the vertical height hv of at least one of the side frame sections 13a, 13b. For example, the inter-frame pivot axis Pa, Pb may be provided vertically centrally relative to at least one, preferably both, of the side frame sections 13a, 13b.

[0080] At the inter-frame pivot joint 131a, 131b, a parallel linkage 141, 141E is provided, wherein one of the lower links 1411 (or a first fork portion of a single link 1411 E) is connected to a first one of the side frame sections 13a and another one of the lower links 1412 (or a second fork portion of a single link 1411 E) is connected to a second one of the side frame sections 13b. Hence, the parallel linkage 141, 141E straddles the inter-frame pivot axis Pa, Pb.

[0081] Referring to figs 6a-6b, connections 14111, 14121 of the lower links 1411, 1412 to the side frame sections 13a, 13b may be provided at approximately the same vertical level. For example, lower link pivot axes Al provided by the lower link connections 14111, 14121 may be vertically aligned with (albeit extending perpendicular to) the inter-frame pivot axis Pa, Pb.

[0082] Preferably, the lower link pivot axes Pa, Pb should be vertically spaced from the inter frame pivot axis by less than 50 % of the frame height hv, preferably less than 30 %, less than 10 % or less than 5 %.

[0083] At least one of the connections 14111, 14121 may be provided with joint bearings, i.e. bearings having the capability to absorb some angular displacement relative to at least one of the lower link pivot axes Al. The bearing(s) may be roller bearings or plain bearings.

[0084] At least one of the connections (not shown) of the respective biasing device 142 may also be provided with joint bearings.

[0085] In figs 6a-6b, the frame sections 13a, 13b are illustrated in a state where they are oriented in parallel with each other, as would be the case when the agricultural implement is positioned on a flat surface.

[0086] In figs 7a-7b the frame sections 13a, 13b are illustrated in a state where they are oriented in a mutually downwardly concave state, as would be the case when the agricultural implement is positioned on an upwardly convex surface.

[0087] In figs 8a-8b the frame sections 13a, 13b are illustrated in a state where they are oriented in a mutually downwardly convex state, as would be the case when the agricultural implement is positioned on an upwardly concave surface.

[0088] With the lower link pivot axes Al positioned vertically close to the inter-frame pivot axis Pa, Pb and a limited (< + / - 10 deg) pivoting about the inter-frame pivot axis Pa, Pb, the relative movement of the connections 14111, 14121 along the lower link pivot axes Al is small enough to be managable by the connections 14111, 14121.

[0089] Optionally, the lower links 1411, 1412 may be made slightly flexible in the direction of the lower link pivot axes Al.

[0090] Yet optionally, the connections 14111, 14121 may provide some axial play along the lower link pivot axes Al.

[0091] It is understood that these connections 14111, 14121 may be desiged according to the same principles regardless of whether the links are short (1411, 1412) or long (1411E).

[0092] The upper link 1413, 1413E may be connected to one or both of the side frame sections 13a, 13b.

[0093] Referring to figs 9a-9b, lOa-lOb and lla-llb, there is illustrated an embodiment in which the upper link 1413, 1413E is connected to both side frame sections 13a, 13b. It is understood that this connection may be desiged according to the same principles regardless of whether the link is short (1413) or long (1413E).

[0094] In the illustrated embodiment, a connection flange 133a, 133b is provded on each of the side frame sections 13a, 13b.

[0095] The forward portion of the upper link 1413, 1413E is pivotably connected to a rod 14134. This connection 14133 may be provided with a joint bearing, or as a rigid bearing. Optionally, biasing devices (not shown) may be provided to ensure that the rod and / or the upper link 1413, 1413E maintains a predetermined axial position relative to the flanges 133a, 133b.

[0096] Connections 14131, 14132 between the rod 14134 and one or both of the flanges 133a, 133b may be provided by joint bearings. Optionally, one or both of the connections 14131, 14132 may allow some axial play along the rod 14134, e.g. by the connection between the joint bearing and the rod 14134 not being axially fixed relative to the rod 14134. One of the connections 14131, 14132 may thus be fixed relative to the rod 14134.

[0097] While figs 9a-9b illustrate the frame sections 13a, 13b when in the planar relative positions, corresponding to figs 6a-6b, figs lOa-lOb illustrate the frame sections 13a, 13b in a mutually downwardly concave state, corresponding to figs 7a-7b. As is highlighted by the dashed ring in fig. 10b, the rod 14134 has moved axially relative to connection 14131, such that its protrusion towards the left in the fig. 10b is less than its corresponding protrusion in fig. 9b.

[0098] Correspondingly, in figs lla-llb, which illustrate the frame sections 13a, 13b in a mutually downwardly convex state, corresponding to figs 8a-8b, the rod 14134 extends further to the left relative to the connection 14131 than in figs 9a-9b.

[0099] Hence, the connection between the upper link 1413, 1413E and the frame sections 13a, 13b is capable of absorbing the offsets created by the relative pivoting of the frame sections 13a, 13b about the inter-frame pivot axis Pa, Pb.

[0100] Referring to figs 12a-12b, 13a-13b and 14a-14b, there is illustrated an embodiment in which the upper link 1413, 1413E is connected to only one of the side frame sections 13a, 13b. It is understood that this connection may be desiged according to the same principles regardless of whether the link is short (1413) or long (1413E).

[0101] Lower links 1411, 1411E and connections 14111, 14121 may be designed in the same manner as disclosed with reference to figs 2-llb.

[0102] A mounting flange 134 may thus be provided on one of the side frame sections 13a, 13b joined by an inter-frame pivot joint 131a, 131b and near said interframe pivot joint 131a, 131b.

[0103] This mounting flange 134 may extend upwardly from the side frame section 13a and optionally also laterally towards the other one of the side frame sections 13b. For example, the mounting flange 134 may comprise an upwardly extending portion and a laterally extending portion, as illustrated in fig 12a.

[0104] A connection 14135 for the upper link 1413, 1413E may be provided at a distal (relative to the side frame section 13a, 13b) portion of the mounting flange 134, in particular portion of mounting flange closest to the other one of the frame sections.

[0105] The connection 14135 may comprise a joint bearing. It may be advantageous to provide a joint bearing also at the other end of the upper link 1413, 1413E, such as where it connects to the output unit frame 140.

[0106] The connection 14135 may be laterally aligned with the inter-frame pivot axis Pa, Pb. Hence, the mounting flange 134 may extend laterally so as to partially bridge the gap between the side frame sections 13a, 13b.

[0107] It is possible to design one or both of the lower links 1411, 1412, and optionally also the upper link 1413, with some lateral resilience so as to allow them to yield slightly as the side frame sections 13a, 13b pivot relative to each other.

[0108] Alternatively, or as a supplement, it is possible to provide the lower link connectors 14111, 14121 with some resilience, e.g. by means of resilient mounts, or by allowing a small play in the respective connector 14111, 14121.

Claims

CLAIMS1. An agricultural implement (1), comprising an implement frame (10, 11, 13a, 13b, 13c) having:a first side frame section (13a; 13b), anda second side frame section (13b; 13c), which is pivotably connected to the first side frame section (13a; 13b) about an inter-frame pivot axis (Pa; Pb) which is horizontal and parallel with a working direction (Dw) of the agricultural implement (1),wherein each of the side frame sections (13a, 13b, 13c) carryies a plurality of tool units (14, 14a-14j), andwherein at least one of the tool units (14, 14a-14j) is connected to the implement frame by a parallel linkage (141) comprising at least two lower links (1411, 1412) and at least one upper link (1413),characterized in thata first one of the lower links (1411, 1412) is pivotably connected to the first side frame section (13a; 13b),a second one of the lower links (1411, 1412) is pivotably connected to the second side frame section (13b; 13c),the upper link is (1413) pivotably connected to at least one of the first side frame section (13a; 13b) and the second side frame section (13b; 13c), andthe lower links (1411, 1412) connect to the respective side frame section (13a, 13b) at approximately a same vertical level as the inter-frame pivot axis.

2. The agricultural implement (1) as claimed in claim 1, wherein the lower links (1411, 1412) connect to the respective side frame sections (13a, 13b, 13c) within a frame height (hv) of at least one of the side frame sections (13a, 13b, 13c).

3. The agricultural implement (1) as claimed in claim 2, wherein the lower links (1411, 1412) connect to the respective side frame sections (13a, 13b, 13c) within a vertical distance from the inter-frame pivot axis (Pa, Pb), which is lessthan about 50 % of the frame height, preferably less than about 25 % of the frame height, less than about 10 % of the frame height or less than about 5 %.

4. The agricultural implement (1) as claimed in any one of the preceding claims, wherein at least one of the lower links (1411, 1412) and the inter-frame pivot axis (Pa) is positioned vertically centrally of at least one of the side frame sections (13a, 13b, 13c).

5. The agricultural implement (1) as claimed in any one of the preceding claims, wherein the tool units (14, 14a-14j) comprise at least some tool units (14, 14a-14j), which are in the form of output units, configured for distributing a product to ground over which the agricultural implement (1) travels.

6. The agricultural implement (1) as claimed in any one of the preceding claims, wherein the side frame sections (13a, 13b, 13c) are configured to allow a limited pivoting action about the inter-frame pivot axis, preferably of less than about + / - 30 degs, less than about + / - 20 degs, less than about + / - 15 degs, less than about + / - 10 degs or less than about + / - 5 degs.

7. The agricultural implement (1) as claimed in any one of the preceding claims, wherein each of the tool units (14, 14a-14j) is connected to the implement frame by a respective parallel linkage (141) comprising at least two lower links (1411, 1412) and at least one upper link (1413).

8. The agricultural implement (1) as claimed in any one of the preceding claims, wherein laterally adjacent tool units (14, 14a-14j) present parallel linkages of different lengths, such that adjacent tool units (14, 14a-14j) are longitudinally offset along the working direction (Dw).

9. The agricultural implement (1) as claimed in any one of the preceding claims, wherein the parallel linkage (141), the first and second lower links (1411, 1412) of which connect to the first and second side frame sections (13a, 13b, 13c), respectively, is longer than those of immediately laterally adjacent tool units (14, 14a-14j).1710. The agricultural implement (1) as claimed in any one of the preceding claims, wherein the lower links (1411, 1412) are fixedly connected to each other, in particular formed in one piece.

11. The agricultural implement (1) as claimed in any one of the preceding claims, further comprising at least one actuator (132a, 132b) configured for controlling a movement about the inter-frame pivot axis (Pa).

12. The agricultural implement (1) as claimed in any one of the preceding claims, wherein one of the first side frame section (13a; 13b) and the second side frame section (13b; 13c) comprises a mounting flange (133a, 133b), to which the upper link (1413) is pivotably connected.

13. The agricultural implement (1) as claimed in claim 12, wherein only one of the first side frame section (13a; 13b) and the second side frame section (13b; 13c) presents the mounting flange (133a, 133b).

14. The agricultural implement (1) as claimed in claim 13, wherein the mounting flange (133a, 133b) presents a portion, which extends laterally towards the other one of the first side frame section (13a; 13b) and the second side frame section (13b; 13c), and to which the upper link (1413) is pivotably connected.

15. The agricultural implement (1) as claimed in claim 12, wherein both of the first side frame section (13a; 13b) and the second side frame section (13b; 13c) presents a respective mounting flange (133a, 133b) and wherein the upper link (1413) is pivotably connected to both of the mounting flanges (133a, 133b).

16. The agricultural implement (1) as claimed in claim 13, wherein a pivot rod (14134) is pivotably connected and axially fixed to one of the mounting flanges (133a, 133b) and pivotably and axially movably connected to the other one of the mounting flanges (133a, 133b), wherein the upper link (1413) is connected to the pivot rod (14134).1817. A method of operating an agricultural implement (1), having an implement frame (10, 13a, 13b, 13c) comprising:a first side frame section (13a; 13b),a second side frame section (13b; 13c), which is pivotably connected to the first side frame section (13a; 13b) about an inter-frame pivot axis (Pa, Pb) which is horizontal and parallel with a working direction (Dw) of the agricultural implement (1),wherein each of the side frame sections (13a, 13b, 13c) carryies a plurality of tool units (14, 14a-14j), andwherein at least one of the tool units (14, 14a-14j) is connected to the implement frame by a parallel linkage (141) comprising a pair of lower links (1411, 1412) and at least one upper link (1413),the method comprising:causing the side frame sections (13a, 13b, 13c) to pivot relative to each other about the inter-frame pivot axis (Pa, Pb), andcausing the parallel linkage (141) to pivot relative to the side frame sections (13a, 13b, 13c) about a pair of lower link pivot axes (Al), that are vertically aligned with the inter-frame pivot axis (Pa, Pb) and that are connected to a respective one of the side frame sections (13a, 13b, 13c).

Images